Apparatus and method for dispensing propane tanks

ABSTRACT

A method and apparatus for dispensing propane filled containers. An enclosure has a conveying line with holders upon which propane filled containers rest. The enclosure has an opening closable by a door actuated upon command by the user. Upon opening of the door, an empty propane container may be inserted into the enclosure to rest upon a holder with the conveying line then being activated to align a new holder with a filled propane container adjacent the enclosure opening allowing the user to remove the filled container.

BACKGROUND OF THE INVENTION

[0001] The present invention relates generally to the field of propane tanks and dispensing machines.

DESCRIPTION OF THE PRIOR ART

[0002] Propane is a liquefied petroleum gas and is stored in a variety of tanks for use in industrial and residential use. Upon exiting the pressurized tank, the propane changes state from a liquid to gas. The residential application of propane includes use as a fuel for cooking grills and a variety of appliances. The U.S. Department of Transportation has established standards for the tanks which are referred to as D.O.T. containers or cylinders. One such tank 20, illustrated in FIG. 1, includes a cylindrical and hollow main body 21 having a rounded bottom end resting upon and fixedly attached to a ring 22. The ring provides a base for tank 20 to rest. Gas within the tank is controllably released via a standard, commercially available, gas valve 23 mounted atop the tank. A valve safety wall 24 is fixedly mounted atop the tank and partially surrounds valve 23. A plurality of slots or openings 25 are provided in wall 24.

[0003] A current practice is for the user to take an empty propane tank to a tank servicing location, such as a grocery store, a gasoline filling station or other retail establishment, and to trade in the empty tank for a propane filled tank. Generally, the propane servicing is provided by the retail establishment as a sideline with the tanks being stored externally of the building for safety reasons. Tanks typically are stored in a steel cage and may also include a central supply of propane utilized to fill the smaller tanks. Thus, the current procedure is for the retail salesman to take time away from the principal business, exiting the building, opening the tank storage cage and inserting the empty tank while retrieving a propane filled tank. In the meantime, additional retail personnel are required within the building to service the principal customers and to monitor the checkout lines. What is needed is a personnel-free, automatic machine for receiving the empty tank and for dispensing a propane filled tank. Disclosed is such a combination and method.

SUMMARY OF THE INVENTION

[0004] One embodiment of the present invention is the combination of a plurality of containers filled with propane and a dispensing machine for holding and dispensing one at a time the containers. A conveying line in the machine is adapted to move and dispense the containers filled with propane and for receiving the empty tanks. An authorization device, upon receipt of the data from a purchaser, will issue a signal to the conveying line to move the containers.

[0005] A further embodiment of the present invention is a method of dispensing tanks of propane comprising the steps of providing a machine with a conveying line for storing tanks of propane. The machine has a dispensing area adjacent the conveying line for mounting tanks of propane onto the conveying line. The conveying line positions the filled tanks at the area and receives the empty tanks.

[0006] It is an object of the present invention to provide the combination of propane filled containers with a machine for automatically dispensing the containers.

[0007] A further object of the present invention is to provide an apparatus to dispense propane filled tanks while receiving empty tanks.

[0008] In addition, it is an object of the present invention to provide a new and improved method of dispensing tanks of propane.

[0009] Related objects and advantages of the present invention will be apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a front view of a conventional D.O.T. propane filled tank.

[0011]FIG. 2 is a front view of the apparatus for dispensing propane filled containers.

[0012]FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2 and viewed in the direction of the arrows showing the conveying line.

[0013]FIG. 4 is a schematic view showing the propane tanks mounted on the conveying line of FIG. 3.

[0014]FIG. 5 is a fragmentary cross-sectional view showing the mounting of a propane tank taken along line of 5-5 of FIG. 4 and viewed in the direction of the arrows.

[0015]FIG. 6 is a fragmentary cross-sectional view showing the mounting of a propane tank taken along line of 6-6 of FIG. 4 and viewed in the direction of the arrows.

[0016]FIG. 7 is a side view of a propane tank and holder taken along the line of 7-7 of FIG. 6 and viewed in the direction of the arrows.

[0017]FIG. 8 is an enlarged and fragmentary cross-sectional view of one of the holder arms taken along the line of 8-8 of FIG. 7 and viewed in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[0019] Referring now more particularly to FIG. 2, there is shown an apparatus 30 for dispensing propane filled containers and for receiving empty propane containers. Apparatus 30 includes a main housing 31 forming an enclosure for the tanks with housing 31 restable upon ground 32. An alternate embodiment includes a housing 31 having a plurality of wheels rotatably mounted to the bottom of the housing to allow the apparatus to be hitched to a vehicle and pulled to the location of operation. For example, the apparatus may be positioned in a parking lot associated with a particular retail establishment. Preferably, stanchions 33 are attached to housing 31. For example, the stanchion may include an upright post fixedly mounted atop a stanchion frame 34 pivotally attached via a conventional hinge 35 to the housing. Thus, the stanchions may be pivoted inward as the apparatus is being towed to the particular location. Once the apparatus is appropriately located, the stanchions may be pivoted outward as shown in FIG. 2.

[0020] Housing 31 includes an opening 36 through which the propane tanks are dispensed and the empty tanks are returned. A door 37 is slidably mounted within the housing to close the opening except during the dispensing and retrieval operation. A conventional authorization device 38 is provided on the exterior wall of the housing for use by the purchaser to authorize and actuate the internal dispensing and retrieval mechanism. Activation device 38 may include a conventional key pad 39 and a credit card or currency receiving slot 40. Such activation devices are commercially available and are found on automatic teller machines, as well as various vending machines. In its simplest form, device 38 and key pad 39 is replaced by an on/off switch to control flow of electricity to a motor activating a conveying line to move and dispense the containers.

[0021] Housing 30 includes a top wall 41 (FIG. 3) and bottom wall 42 joined to the side walls (not shown), as well as the front wall 43 and rear wall 44 forming an enclosure 45 in which the conveying line and tanks are located.

[0022] The mechanism for holding and dispensing the propane filled containers and for receiving and storing the empty propane containers includes a pair of continuous parallel roller chains with one such continuous roller chain 46 shown in FIG. 4 wound in a circuitous manner around a plurality of idle sprockets 47. The chains are in meshing engagement with a pair of drive sprockets. The drive sprockets are driven by second chains, in turn, engaged by the output drive sprockets of a conventional electric motor 85. The various propane filled tanks are removably mounted to the chains and are movable past opening 36 providing both a dispensing area in which the propane filled containers are dispensed and a receiving area whereat the empty tanks are inserted into the enclosure and mounted to the chains.

[0023] In the embodiment shown in the drawings (FIG. 4) twenty-one holders are provided for holding a combination of filled and empty tanks. The holders are identical with one such holder 55 being shown in FIGS. 5-7. The holders are not shown in FIGS. 3 and 4 to more clearly illustrate the circuitous path of the conveying line. Holder 55 includes a bottom wall 56 (FIG. 7) upon which ring 22 of the propane tank sits and rests. Wall 56 is fixedly attached to an upwardly extending wall 57 having a horizontal wall 58 integrally joined thereto with the distal end 59 of wall 58 extending vertically. Thus, end 59 of wall 58 may be slipped into slot 25 of valve protecting wall 24 thereby forming a hooked shape end releasably engaged with the slot and valve wall. Wall 58 may be elastically pushed downwardly to align distal end 59 which is sized smaller than slot 25 thereby enabling the tank to be disengaged from end 59. Wall 56 has an upwardly turned distal end 60 sized to center the main body of the tank between distal end 60 and vertical wall 57.

[0024] A pair of arms 61 and 62 (FIG. 5) have proximal ends fixedly joined to vertical wall 57 with arms 61 and 62 extending at least partially around the tank main body thereby grasping the tank on its opposite sides. At the distal end of each arm is located a spring biased, button shaped tank engager to releasably hold the tank therebetween. For example, arm 61 has a proximal end 70 (FIG. 7) with engager 71 movably mounted thereto. The engager includes a concave shaped button 72 (FIG. 8) fixedly mounted to pin 73 slidably mounted to distal end 70. A helical spring 74 is located between button 72 and distal end 70 and normally urges the button against the outer surface of the container 20. A conventional fastening device 75 extends through pin 73 preventing the disengagement of the pin relative to distal end 70. Helical spring 74 may be compressed to allow container 20 to be moved between the engagers mounted to the distal ends of arms 61 and 62.

[0025] Chain mounts 76 and 77 (FIG. 6) are mounted respectively to arms 62 and 61 and respectively to the pair of parallel chains 46 and 78. Chain mount 76 and 77 are standard roller chain mounts and are secured to chains 46 and 78 while being pivotally mounted to arms 62 and 61 allowing the holder with container to pivot as the chains move through the circuitous path depicted in FIG. 4. The pair of chains 46 and 78 are in meshing engagement and held by a plurality of idle sprockets 47 rotatably mounted to suitable beams within the apparatus.

[0026] A pair of drive sprockets 80 and 81 (FIG. 6) are rotatably mounted by shaft 82 to a pair of upstanding beams 83 and 84 with the shaft fixedly connected to the rotatable output drive shaft of a conventional electric motor 85 mounted within the apparatus. A second pair of chains 86 and 87 are in meshing engagement with sprockets 80 and 81 and, in turn, with a second pair of sprockets 88 and 89. Sprockets 88 and 89 are rotatably mounted to beams 83 and 84 by shafts 90 and 91 having at their opposite ends a pair of sprockets 92 and 93 in driving engagement with chains 46 and 78. Thus, by operation of motor 85, sprockets 92 and 93 are caused to rotate thereby moving chains 46 and 78 and causing the containers to move through the path depicted in FIG. 4.

[0027] In the embodiment depicted in FIG. 4, a total of twenty-one holders are pivotally mounted to chains 46 and 78 with the containers always being positioned in their normal vertical or upright position even though the chains move horizontally and vertically through the path. The container holders are pivotally mounted to chain mounts 76 and 77 thereby allowing the containers to remain upright. Arms 61 and 62 extend sufficiently apart from wall 57 (FIG. 7) to position the container engagers 71 past the center line of each container with chains 46 and 78 being located between the walls 57 of each holder and the container engagers 71 thereby ensuring the containers remain in an upright position.

[0028] Twenty propane filled containers are initially mounted to the holders attached to the conveying line formed by chains 46 and 78. For example, all of the containers depicted in FIG. 4 represent containers filled with propane with the exception of container 94 located adjacent opening 36. The holder located adjacent opening 36 is initially not provided with a container. Upon operation, the user inserts a credit card or currency in slot 40 operating keypad 39 (FIG. 2) thereby causing door 37 to slide upwardly by means of a linear door actuator 102. Linear door actuator 102 (FIG. 3) has a motor driven, threaded, rotatable rod 105 extending through an internally threaded, captive nut 106 mounted by bracket 107 to door 37 for raising and lowering the door. The user then inserts the return empty propane container 94 through opening 36 and on to the holder. A suitable container detector, such as a laser emitter and sensor, detects the presence of the container on the holder thereby activating the linear door actuator causing door 37 to close opening 36 while simultaneously activating motor 85. Activation of motor 85 causes chains 46 and 78 to move thereby moving filled propane container 95 to a position adjacent and behind the closed door 37. The filled container is detected thereby actuating the linear door actuator and causing door 37 to slidably move upwardly revealing filled container 95. The user grasps container 95 and removes same from its holder. Upon removal of the filled container, the door closes and is ready for the next customer.

[0029] The method of dispensing tanks of propane thus comprises the steps of providing a machine with a conveying line for storing tanks of propane with the machine having a dispensing area 36 adjacent the conveying lines formed by chains 46 and 78. Tanks of propane are mounted onto the conveying line with the conveying line then being moved to position a tank of propane adjacent the dispensing area for removal therefrom. The empty tanks of propane are inserted onto the conveying line. The tanks of propane rest on the bottom walls of the tank holders whereas the top ends of the tanks are hooked onto a hook-shaped wall provided at the top of the holder. Sideways pressure is applied to each tank by the side arms and engagers 71.

[0030] The embodiment of the combination of the dispensing machine and containers depicted in the drawings is designed to dispense one at a time a container filled with propane. The tank holders not only hold the filled containers but also act as receivers to receive and store the containers when emptied.

[0031] Various auxiliary equipment may be provided with the dispensing machine. For example, a gas detection sensor 101 is mounted within enclosure 45 to sense escape of propane from the containers and is connected by suitable circuitry to motor 85 to prevent movement of chains 46 and 78 upon the sensing of propane escape. Commercially available gas detection devices are available and are operable to activate at 90,000 parts per million to thereby disrupt electrical current to motor 85 and prevent movement of the conveying line.

[0032] In addition to the gas detection device, a conventional heat sensor 103 is mounted within enclosure 45 and may be set to activate an alarm once the temperature reaches a predetermined level, for example 140 degrees Fahrenheit. The heat sensor alarm and gas detection device may be connected to an automatic telephone system for alerting the home office as well as the fire department.

[0033] Further, an automatic fire extinguisher may be mounted within enclosure 45. Commercial fire extinguishers having a dry chemical for release at a predetermined temperature, for example 145 degrees Fahrenheit may be connected to the heat sensor for activation.

[0034] A conventional programmable controller may be utilized to connect the various sensors, extinguisher, automatic phone dialing equipment, linear door actuator, and for a control of conveying line motor 85.

[0035] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. 

What is claimed is:
 1. The combination of: a plurality of containers filled with propane; a dispensing machine for holding and dispensing one at a time said containers filled with propane; a conveying line associated with said machine adapted to contact and move said containers filled with propane to dispense said containers; and, an authorization device upon command from a purchaser to issue a command to said conveying line to move and dispense said containers filled with propane.
 2. The combination of claim 1 wherein: said conveying line includes a receiver to receive, move and store said containers when empty.
 3. The combination of claim 2 wherein: said dispensing machine includes a dispensing and receiving area whereat said containers filled with propane are removed from said conveying line and said containers when empty are mounted on said conveying line, said conveying line includes a plurality of container holders movable one at a time past said area allowing mounting of said containers when empty thereon and removal of containers filled with propane therefrom.
 4. The combination of claim 3 wherein: said containers each include a tank with a valve mounted thereatop and a valve protecting wall mounted atop said tank and at least partially surrounding said valve, said valve protection wall includes a slot, said container holders each include a bottom wall upon which said tank may sit and a top hook releasably engaged with said slot.
 5. The combination of claim 4 wherein: said container holders each include a rear wall joining said bottom wall to said top hook and a pair of arms extending forwardly from said rear wall to at least partially surround said tank, said arms including a pair of spring biased tank engagers holding said tank on said bottom wall until removed therefrom, said conveying line further includes a continuous chain and a chain driver with said container holders mounted to said chain and said driver moving said chain to position said container holders one at a time at said area.
 7. The combination of claim 3 and further comprising: a movable door normally closing said area but opening upon command by said authorized device.
 8. The combination of claim 1 and further comprising: a gas detection sensor in said machine to sense escape of propane from said containers and to limit operation of said conveying line.
 9. The combination of claim 1 and further comprising: a heat sensor in said machine to sense heat.
 10. The combination of claim 1 further comprising: a stanchion mounted to said machine to protect said machine from external impact.
 11. A apparatus for dispensing propane filled containers and for receiving empty propane containers comprising: a mechanism for holding and dispensing propane filled containers and for receiving and storing empty propane containers, said mechanism having a dispensing area at which said propane filled containers are dispensed; a conveying line mounted on said mechanism and adapted to grip and move said propane filled containers one at a time to said dispensing area; and an authorization device upon activation by a purchaser to authorize said conveying line to dispense a propane filled containers.
 12. The apparatus of claim 11 and further comprising: said mechanism includes an enclosure in which said conveying line is movably mounted, said enclosure having an opening through which respectively said empty propane containers may be inserted into said enclosure and propane filled containers may be removed, said enclosure including a door movably mounted thereto and normally closing said opening until said authorization device activates.
 13. The apparatus of claim 12 wherein: said conveying line includes a continuous chain, a plurality of container holders mounted to said chain, and a chain driver engaged with said chain to move said holders to said opening one at a time to allow removal of propane filled containers and insertion of empty propane containers relative to said enclosure.
 14. The apparatus of claim 13 and further comprising: gas detection sensor in said enclosure to sense escape of propane from said propane filled containers and to limit operation of said conveying line; and a heat sensor in said enclosure to sense heat.
 15. A method of dispensing tanks of propane comprising the steps: providing a machine with a conveying line for storing tanks of propane, said machine having a dispensing area adjacent said conveying line; providing tanks of propane onto said conveying line; moving said conveying line to position a tank of propane at said area; and removing a tank of propane from said conveying line at said area.
 16. The method of claim 15 and further comprising the step of: inserting empty tanks of propane onto said conveying line.
 17. The method of claim 16 and further comprising the step of: providing tank holders with bottom walls, top hooks and side arms on said conveying line; and wherein said mounting step includes the sub-steps of: resting said tanks of propane on said bottom walls; hooking said tanks of propane on said top hooks; and, applying sideways pressure to said tanks of propane by said side arms. 